Split deopt-after and deopt-before handling:

runtime/vm/deopt_instructions.h

Index: runtime/vm/deopt_instructions.h
===================================================================
--- runtime/vm/deopt_instructions.h	(revision 11719)
+++ runtime/vm/deopt_instructions.h	(working copy)
@@ -88,7 +88,8 @@
 
  protected:
   enum Kind {
-    kSetRetAddress,
+    kSetRetAfterAddress,
+    kSetRetBeforeAddress,
     kCopyConstant,
     kCopyRegister,
     kCopyXmmRegister,
@@ -123,10 +124,16 @@
         object_table_(object_table),
         num_args_(num_args) {}
 
-  // Will be neeeded for inlined functions, currently trivial.
-  void AddReturnAddress(const Function& function,
-                        intptr_t deopt_id,
-                        intptr_t to_index);
+  // Return address before instruction.
+  void AddReturnAddressBefore(const Function& function,
+                              intptr_t deopt_id,
+                              intptr_t to_index);
+
+  // Return address after instruction.
+  void AddReturnAddressAfter(const Function& function,
+                             intptr_t deopt_id,
+                             intptr_t to_index);
+
   // Copy from optimized frame to unoptimized.
   void AddCopy(const Location& from_loc,
                const Value& from_value,